The stomach wall or the like of a patient is conventionally observed by inserting an endoscope nasally or orally into the stomach, or the like, but this method can cause discomfort to the patient. Consequently, it has become necessary in recent practice to make a gastrostomy catheter indwelling in a gastrostomy hole formed in the patient's body and to observe the interior of the stomach by passing an endoscope inside said gastrostomy catheter so as to confirm the indwelling position of the gastrostomy catheter. In such cases it is necessary to be able to change the orientation of the tip end of the endoscope for observation in various directions in order to accurately check the state of the interior the stomach and to confirm the indwelling position of the gastrostomy catheter. Consequently, a bending instrument for an endoscope in which the direction of orientation of the tip end of the endoscope can be changed is used (see Japanese Unexamined Patent Application Publication H8-280694, for example).
This bending sheath for a probe (bending instrument for an endoscope) has a configuration in which one end of a metal wire is fixed by soldering to a metal fixture of the bending sheath which is provided with the metal fixture at one end and provided with a metal fixture for the forceps hole at the other end, and a metal cap is fixed by soldering to the other end of the wire. A probe (endoscope) to which this bending sheath for a probe is fitted comprises an ultrasonic probe which is provided with an ultrasonic oscillator at the tip end, and said ultrasonic probe is connected to a device which can produce images from ultrasonic tomographic images on an ultrasonic monitor by sending and receiving ultrasonic waves to the patient via the ultrasonic oscillator.
Consequently, the ultrasonic probe is inserted into the bending sheath from the metal fixture for the forceps hole and the tip end thereof runs into the inner wall of the cap, after which, with continued insertion of the ultrasonic probe, the portion at the tip end of the ultrasonic probe starts to bend so as to move away from the axial direction of the bending sheath. By means of this, the tip end of the ultrasonic probe can be oriented in the required direction, making it possible to obtain ultrasonic tomographic images of that area.
However, with the bending sheath for a probe described above, the bending sheath and the cap are joined to the wire, and therefore a portion of the ultrasonic probe lying between the bending sheath and the cap is exposed to the outside. Consequently, the exposed portion of the ultrasonic probe comes into direct contact with bodily fluids etc. from various parts of the body during use, and becomes soiled. Furthermore, with the bending sheath for a probe described above, the cap comprises a member that is closed at its tip end, and therefore it cannot be used with an endoscope for capturing images by focusing using a lens.
The present invention has been devised in order to deal with the problems described above, and it aims to provide a bending instrument for an endoscope with which it is possible to observe various parts inside the stomach using an endoscope, without soiling of the endoscope, and an endoscope set which employs this.